freebsd-nq/sys/dev/mailbox/arm/arm_doorbell.h
Ruslan Bukin 54b96380f5 Add support for ARM System Control and Management Interface (SCMI) v3.1.
The SCMI specification describes a set of standard interfaces for power,
performance and system management.

SCMI is extensible and provides interfaces to access functions which are
often implemented in firmwares in the System Control Processor (SCP).

This implements Shared Memory-based transfer, which is one of the ways on
how messages are exchanged between agents and the platform.

This includes a driver for ARM Message Handling Unit (MHU) Doorbell, which
is a mechanism that the caller can use to alert the callee of the presence
of a message.

The support implements clock management interface. For instance this allows
us to control HDMI pixel clock on ARM Morello Board.

Tested on ARM Morello Board.

Obtained from: CheriBSD
Differential Revision:	https://reviews.freebsd.org/D37316
Reviewed by:	manu
Sponsored by:	UKRI
2022-12-19 22:28:21 +00:00

52 lines
2.0 KiB
C

/*-
* SPDX-License-Identifier: BSD-2-Clause
*
* Copyright (c) 2022 Ruslan Bukin <br@bsdpad.com>
*
* This work was supported by Innovate UK project 105694, "Digital Security
* by Design (DSbD) Technology Platform Prototype".
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
* $FreeBSD$
*/
#ifndef _ARM64_SCMI_ARM_DOORBELL_H_
#define _ARM64_SCMI_ARM_DOORBELL_H_
struct arm_doorbell {
device_t dev;
device_t db_dev;
int chan;
int db;
void (*func)(void *);
void *arg;
};
void arm_doorbell_set(struct arm_doorbell *db);
int arm_doorbell_get(struct arm_doorbell *db);
struct arm_doorbell * arm_doorbell_ofw_get(device_t dev, const char *name);
void arm_doorbell_set_handler(struct arm_doorbell *db, void (*func)(void *),
void *arg);
#endif /* !_ARM64_SCMI_ARM_DOORBELL_H_ */